TY - JOUR
T1 - B-cell activation with CD40L or CpG measures the function of B-cell subsets and identifies specific defects in immunodeficient patients
AU - Marasco, Emiliano
AU - Farroni, Chiara
AU - Cascioli, Simona
AU - Marcellini, Valentina
AU - Scarsella, Marco
AU - Giorda, Ezio
AU - Piano Mortari, Eva
AU - Leonardi, Lucia
AU - Scarselli, Alessia
AU - Valentini, Diletta
AU - Cancrini, Caterina
AU - Duse, Marzia
AU - Grimsholm, Ola
AU - Carsetti, Rita
N1 - © 2016 The Authors. European Journal of Immunology published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
PY - 2016/11/1
Y1 - 2016/11/1
N2 - Around 65% of primary immunodeficiencies are antibody deficiencies. Functional tests are useful tools to study B-cell functions in vitro. However, no accepted guidelines for performing and evaluating functional tests have been issued yet. Here, we report our experience on the study of B-cell functions in infancy and throughout childhood. We show that T-independent stimulation with CpG measures proliferation and differentiation potential of memory B cells. Switched memory B cells respond better than IgM memory B cells. On the other hand, CD40L, a T-dependent stimulus, does not induce plasma cell differentiation, but causes proliferation of naïve and memory B cells. During childhood, the production of plasmablasts in response to CpG increases with age mirroring the development of memory B cells. The response to CD40L does not change with age. In patients with selective IgA deficiency (SIgAD), we observed that switched memory B cells are reduced due to the absence of IgA memory B cells. In agreement, IgA plasma cells are not generated in response to CpG. Unexpectedly, B cells from SIgAD patients show a reduced proliferative response to CD40L. Our results demonstrate that functional tests are an important tool to assess the functions of the humoral immune system.
AB - Around 65% of primary immunodeficiencies are antibody deficiencies. Functional tests are useful tools to study B-cell functions in vitro. However, no accepted guidelines for performing and evaluating functional tests have been issued yet. Here, we report our experience on the study of B-cell functions in infancy and throughout childhood. We show that T-independent stimulation with CpG measures proliferation and differentiation potential of memory B cells. Switched memory B cells respond better than IgM memory B cells. On the other hand, CD40L, a T-dependent stimulus, does not induce plasma cell differentiation, but causes proliferation of naïve and memory B cells. During childhood, the production of plasmablasts in response to CpG increases with age mirroring the development of memory B cells. The response to CD40L does not change with age. In patients with selective IgA deficiency (SIgAD), we observed that switched memory B cells are reduced due to the absence of IgA memory B cells. In agreement, IgA plasma cells are not generated in response to CpG. Unexpectedly, B cells from SIgAD patients show a reduced proliferative response to CD40L. Our results demonstrate that functional tests are an important tool to assess the functions of the humoral immune system.
KW - Journal Article
U2 - 10.1002/eji.201646574
DO - 10.1002/eji.201646574
M3 - Article
C2 - 27800605
VL - 47
SP - 131
EP - 143
JO - European Journal of Immunology
JF - European Journal of Immunology
SN - 0014-2980
IS - 1
ER -